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Old 14th March 2013, 07:39 AM   #321
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For those interested here is a pic of my moded one.

Cheers George
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File Type: jpg My 303 200 emailable.jpg (635.7 KB, 373 views)
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Old 15th March 2013, 02:47 AM   #322
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Hi Jeff, wondering if your up to it some more simming, my current tz resistor is 4.7k with 350pf then from TZ into the discrete buffer circuit, more gain again with this setup, your sim should show this.
But I was wondering a 15k and 100pf TZ then into the discrete buffer, what the sim would show up as far as the gain comparison, can it do distortions as well?

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Old 17th March 2013, 04:12 PM   #323
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Originally Posted by georgehifi View Post
Hi Ken it's the Cary CD 303-200 and it comes with digital domain volume, switchable PMD200 hdcd, and I believe a DF1704 under the covers?(pic attached).

Cheers George
Okay, I see. The module in the photo labeled DSP 6 probably contains a DSP chip performing the digital filtering (PMD200) in software, and also implements the digital volume control.

I'm confused about something. Stupidity on my part here, but are the PCM1704 to which you've been referring part of the original Cary player design, or re they part of some external DAC box? If they are a part of the Cary player, are you transmitting their current output signals to some added AD844 board, or are the AD844s also part of the original player?
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Old 17th March 2013, 08:21 PM   #324
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PMD 200 is the real thing not Microsoft software, and from what I gather the DSP cover hides a DF1704 (but don't hold me to that) that's switchable via the remote to the PMD200.

Cheers George
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Old 17th March 2013, 11:05 PM   #325
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George:

To my understanding, the PMD200 was never an actual hardwired chip, like was the PMD100. The 'PMD200' only existed in software as a product. Since Microsoft purchased Pacific Microsonics way back when, I shouldn't be surprised if there is a version ported to Windows PCs. It definitely was ported to DSP ICs as firmware. I believe that the only hardwired (ASIC) HDCD chip was the PMD100. However, I'm open to correction on that.
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Old 17th March 2013, 11:10 PM   #326
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The PMD200 was Pacific Microsonic Devices last/latest HDCD chip an improvment on the PMD100 then they folded.

Cheers George
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Old 17th March 2013, 11:42 PM   #327
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They are still around, but they will cost you.

PMD200 HDCD Decoder IC from Pacific Microsonics | eBay

Cheers George
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Old 18th March 2013, 03:02 AM   #328
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Thanks, for the links, George. I'd never seen photos of a PMD200 IC before, only standard product DSP ICs carrying the firmware. I had thought one would be more likely to find a photo of a unicorn.
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Old 18th March 2013, 03:35 AM   #329
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Isn't that exactly what a PMD200 is? A DSP56300 re-badged by PM?
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Old 18th March 2013, 01:21 PM   #330
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Isn't that exactly what a PMD200 is? A DSP56300 re-badged by PM?
That would comport with what I had always thought, if that is indeed a DSP chip inside the package of that pictured IC. What I didn't realize was that PM had sourced their own brand labeled DSP devices with their HDCD algorithms hard coded on-chip in (P)ROM. I had been under the impression that users were required to directly source the DSP IC from the semiconductor vendor, then license the HDCD code separately from PM, and then integrate the two themselves. I'm not sure how I came by that notion.

Based on those mistaken reasons, I had not been surprised that the PMD200 seemed to be a market failure, relative to the PMD100, despite the technology it embodied. So, then, does anyone know why the PMD200 had nowhere near the market success of the PMD100?
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